Xyleborus volvulus

Taxonomic history

Bostrichus volvulus Fabricius, 1775: 454.

Hylesinus volvulus (Fabricius): Fabricius, 1801: 394.

Xyleborus volvulus (Fabricius): Eggers, 1929: 47.

Synonyms

Xyleborus alternans Eichhoff, 1869: 280. Eggers 1929: 43.

Xyleborus badius Eichhoff, 1869: 280. Wood 1960: 69.

Xyleborus interstitialis Eichhoff, 1878b: 375. Wood 1982: 833.

Xyleborus guanajuatensis Dugès, 1887: 141. Wood 1983: 650.

Xyleborus grenadensis Hopkins, 1915a: 62, 65. Wood 1972: 200.

Xyleborus hubbardi Hopkins, 1915a: 62, 65. Schedl 1952d: 164.

Xyleborus rileyi Hopkins, 1915a: 62, 65. Bright 1968: 1318.

Xyleborus schwarzi Hopkins, 1915a: 62, 65. Bright 1968: 1318.

Xyleborus continentalis Eggers, 1920: 42. Beaver 2011: 285.

Xyleborus silvestris Beeson, 1929: 241. Wood 1989: 177.

Xyleborus granularis Schedl, 1950b: 898. Wood 1989: 177.

Diagnosis

2.5 mm long (mean = 2.5 mm; n = 5); 3.13 times as long as wide. This species is distinguished by the protibiaprotibia:
'tibia of the first pair of legs
obliquely triangular, broadest at distaldistal:
situated away from the body
third; elytralelytral:
'pertaining to the elytra
declivitydeclivity:
downward slope of either the pronotum or elytra
smooth, shiningshining:
appearing glossy or bright in luster; referring to a surface that is polished and reflects light well
(specimen must be dry); declivitaldeclivital:
pertaining to the elytral declivity
interstriae 1, 3 armed with 2–3 pairs of moderate tubercles; interstriaeinterstria:
'longitudinal spaces along the elytra between the striae, which is not as<br /> impressed and bear smaller punctures.
2 sparsely granulategranulate:
'pertaining to a coarse, grainy surface texture'
along its entireentire:
'without marginal teeth or notches
length; and elytraelytron:
' the two sclerotized forewings of beetles that protect and cover the flight wings
unicolorus.
This species is almost identical to X. perforans and can be distinguished by the more elongate form (vs 2.67–2.89 times as long as wide) and by granulesgranule:
'a small rounded protuberance, like grains of sand
along the entireentire:
'without marginal teeth or notches
length of interstriaeinterstria:
'longitudinal spaces along the elytra between the striae, which is not as<br /> impressed and bear smaller punctures.
2.

May be confused with

Xyleborus affinis, X. cognatus, X. ferrugineus, X. festivus, X. perforans, and X. pfeilii

Distribution

Circumtropical. Probably of American origin (Wood 2007Wood 2007:
Wood SL. 2007. Bark and ambrosia beetles of South America (Coleoptera: Scolytidae). Brigham Young University, M.L. Bean Life Science Museum; Provo, 900 p., Gohli et al. 2016). In the study region, recorded from India (Nicobar Is.), Bangladesh, Japan, South Korea, Myanmar, Taiwan, Thailand.

Host plants

strongly polyphagous (Browne 1961bBrowne 1961b:
Browne FG. 1961b. The biology of Malayan Scolytidae and Platypodidae. Malayan Forest Records 22: 1-255., Schedl 1963aSchedl 1963a:
Schedl KE. 1963a. Scolytidae und Platypodidae Afrikas. Band II. Familie Scolytidae (Fortsetzung), Unterfamilie Ipinae (Fortsetzung). Revista de Entomologia de Moccedil;ambique 5: 1-594., as X. torquatus)

Remarks

Specimens from Southeast Asia were not available for examination. The measurements and diagnosis are based off of specimens Panama (Panama) and the United States (Florida).

Wood and Bright (1992) considered reports of the species ranging from Southeast Asia to the southwestern Pacific as referring to X. perforans. Some of the records from the countries of the study region given above may refer to X. perforans (Beaver et al. 2014Beaver et al. 2014:
Beaver RA, Sittichaya W, Liu L-Y. 2014. A synopsis of the scolytine ambrosia beetles of Thailand (Coleoptera: Curculionidae: Scolytinae). Zootaxa 3875: 1-82. http://dx.doi.org/10.11646/zootaxa.3875.1.1). However, molecular studies have confirmed that the species does occur Bangladesh and Thailand (Gohli et al. 2016Gohli et al. 2016:
Gohli J, Selvarajah T, Kirkendall LR, Jordal BH. 2016. Globally distributed Xyleborus species reveal recurrent intercontinental dispersal in a landscape of ancient worldwide distributions. BMC Evolutionary Biology 16: 37. https://doi.org/10.1186/s12862-016-0610-7).

Wood and Bright (1992) postulated that X. pfeilii is a synonym of X. volvulus, and this was further suggested by Gomez et al. (2018). Though appearing quite similar, the protibiaprotibia:
'tibia of the first pair of legs
of these species are different. That of X. pfeilii is distinctly triangular while that of X. volvulus is obliquely triangular. Analysis of COI and CAD sequences has also shown that these species are separate lineages (Cognato et al. in prep) and that X. pfeilii is a good species.

DNA data

Sequences available for COI and CAD.

COI: HM064149

CAD: HM064327